The time for waiting until next year is over, as parity across baseball has created an opening for the Mets to earn a playoff appearance for the first time since 2006.

As baseball’s second half begins, no division leader holds more than a 4½-game lead, and the Mets enter the second half of what already has been a compelling season trailing the division-leading Nationals by just two games. In a year when the Nationals were bestowed a crown in February, it’s the Mets who are in position to grab the division behind a talented rotation.

Nevertheless, it’s the Mets’ bats which threaten to derail their season, and MLB Network analyst and 2004 World Series champion Kevin Millar said they need to be active on the trade market to correct that flaw.

“The Mets need some hitting,” Millar said. “They have to hit. So you’ve got to make something crazy. Get Yasiel Puig and trade one of your young pitchers, or whatever it is.

Yasiel PuigGetty Images

“But they have to get a dynamic, young offensive player, because it’s tough. You’ve got a lot of pitching, but you’ve got to find a way to score a run.”

Scoring runs has been the issue for general manager Sandy Alderson’s team all season. The Mets rank 14th out of 15 NL teams in total offense, while ranking third in the majors with a 3.23 team ERA.

The trio of Jacob deGrom — who in his first All-Star Game struck out the side on just 10 pitches — Matt Harvey and Noah Syndergaard has kept the Mets in games, but an inability to score runs has resulted in frustrating losses.

“You can’t keep grinding everybody and not putting up runs,” said 12-year MLB veteran and current MLB Network analyst Sean Casey. “I think they’ll scuffle [in the second half]. I think their pitching is good, though. The future is bright there.”

Scoring runs has not been a problem across town in The Bronx, where the Yankees completed the first half with a 48-40 record. That’s not quite reminiscent of their dynasty era, but it’s good enough to hold the division lead by 3½ games.

Fueled by the resurgence of Alex Rodriguez, who blasted 18 homers in the first half, and a fully healed Mark Teixeira leading the AL with 62 RBIs, the Yankees rank second in the majors in total offense.

Quietly, it also has been the bounce-back season from Brian McCann that has lengthened manager Joe Girardi’s lineup. After hitting just .232 with 23 homers in the first season of a five-year, $85 million deal, McCann has reverted to his All-Star form this season. Throwing out 40 percent of would-be base stealers — good enough for eighth in the majors — to go along with a .259 batting average, 14 homers and 55 RBIs, McCann has been a strength behind the plate.

Count Casey as someone who believes the Yankees could find themselves atop the division at the season’s conclusion, ending a streak of two straight dark Octobers.

“They keep getting it done,” Casey said. “I think the Yankees have a good shot at that division because it’s not that strong.”

But other storylines of intrigue include the breakout season from Bryce Harper, who may have an outside chance at a Triple Crown — his current .339/.464/.704 slash line at age 22 has been accomplished only by Ted Williams — and the battle for the NL Central.

“With the Cardinals, the Pirates are now breathing down their back,” Millar said. “And you look at the Pirates, they look like the best team in baseball.”

“Now [the Pirates] are making a run at that division,” Casey added. “It’s going to be interesting to watch.”